package org.sun.web.security;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import org.springframework.security.access.SecurityMetadataSource;
import org.springframework.security.access.intercept.AbstractSecurityInterceptor;
import org.springframework.security.access.intercept.InterceptorStatusToken;
import org.springframework.security.web.FilterInvocation;
import org.springframework.security.web.access.intercept.FilterInvocationSecurityMetadataSource;

//implements Filter是servlet的filter类
//MyAuthorizationFilter类，负责过滤url请求
public class MyAuthorizationFilter extends AbstractSecurityInterceptor implements Filter {

	
	private FilterInvocationSecurityMetadataSource securityMetadataSource;
	public FilterInvocationSecurityMetadataSource getSecurityMetadataSource() {
		return securityMetadataSource;
	}

	public void setSecurityMetadataSource(FilterInvocationSecurityMetadataSource securityMetadataSource) {
		this.securityMetadataSource = securityMetadataSource;
	}

	@Override
	public void destroy() {
		// TODO Auto-generated method stub

	}

	@Override
	public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2)
			throws IOException, ServletException {
		FilterInvocation fi=new FilterInvocation(arg0, arg1, arg2);
		InterceptorStatusToken token=super.beforeInvocation(fi);
		
		try {
			fi.getChain().doFilter(fi.getRequest(), fi.getResponse());
		} finally{
			super.afterInvocation(token, null);
		}

	}

	@Override
	public void init(FilterConfig arg0) throws ServletException {
		// TODO Auto-generated method stub

	}

	@Override
	public Class<?> getSecureObjectClass() {
		return FilterInvocation.class;
	}

	@Override
	public SecurityMetadataSource obtainSecurityMetadataSource() {
		return getSecurityMetadataSource();
	}

}
